189 research outputs found
Solution of QCDQED coupled DGLAP equations at NLO
In this work, we present an analytical solution for QCDQED coupled
Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations at the
leading order (LO) accuracy in QED and next-to-leading order (NLO) accuracy in
perturbative QCD using double Laplace transform. This technique is applied to
obtain the singlet, gluon and photon distribution functions and also the proton
structure function. We also obtain contribution of photon in proton at LO and
NLO at high energy and successfully compare the proton structure function with
HERA data \cite{12} and APFEL results \cite{7}. Some comparisons also have been
done for the singlet and gluon distribution functions with the MSTW
results\cite{9}. In addition, the contribution of photon distribution function
inside the proton has been compared with results of MRST \cite{11} and with the
contribution of sea quark distribution functions which obtained by MSTW
\cite{9} and CTEQ6M \cite{14}.Comment: 23 pages, 11 figur
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HARD: Hybrid Adaptive Resource Discovery for Jungle Computing
In recent years, Jungle Computing has emerged as a distributed computing paradigm based on simultaneous combination of various hierarchical and distributed computing environments which are composed by large number of heterogeneous resources. In such a computing environment, the resources and the underlying computation and communication infrastructures are highly-hierarchical and heterogeneous. This creates a lot of difficulty and complexity for finding the proper resources in a precise way in order to run a particular job on the system efficiently. This paper proposes Hybrid Adaptive Resource Discovery (HARD), a novel efficient and highly scalable resource-discovery approach which is built upon a virtual hierarchical overlay based on self-organization and self-adaptation of processing resources in the system, where the computing resources are organized into distributed hierarchies according to a proposed hierarchical multi-layered resource description model. The proposed approach supports distributed query processing within and across hierarchical layers by deploying various distributed resource discovery services and functionalities in the system which are implemented using different adapted algorithms and mechanisms in each level of hierarchy. The proposed approach addresses the requirements for resource discovery in Jungle Computing environments such as high-hierarchy, high-heterogeneity, high-scalability and dynamicity. Simulation results show significant scalability and efficiency of the proposed approach over highly heterogeneous, hierarchical and dynamic computing environments
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A Self-organizing and Self-configuration Algorithm for Resource Management in Service-oriented Systems
With the ever increasing deployment of service-oriented distributed systems in large-scale and heterogeneous computing environments, clustering and communication overlay topology design has become more and more important to address several challenging issues and conflicting requirements, such as efficient scheduling and distribution of services among computing resources, reducing communication cost between services, high performance service and resource discovery while considering both inter-service and inter-node properties and also increasing the load distribution and the load balance. In this paper, a four-stage hierarchical clustering algorithm is proposed which automates the process of the optimally composing communicating groups in a dynamic way while preserving the proximity of the nodes. The simulation results show the performance of the algorithm with respect to load balance, scalability and efficiency
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A Specification-based Anycast Scheme for Scalable Resource Discovery in Distributed Systems
Anycast is a powerful paradigm for managing and locating resources in large scale distributed computing systems. This paper presents a novel specification-based anycasting scheme for resource discovery in such environments. The effectiveness of our proposal is demonstrated through simulation results, in which we observed a remarkable performance enhancement in different aspects (such as discovery latency, discovery cost, discovery load, etc.) over similar non-anycast based discovery methods
Thermosensitive chitosan/poly(N-isopropyl acrylamide) nanoparticles embedded in aniline pentamer/silk fibroin/polyacrylamide as an electroactive injectable hydrogel for healing critical-sized calvarial bone defect in aging rat model
Thermosensitive nanoparticles with phase transition abilities have been considered as suitable materials in biomedical fields, especially drug delivery systems. Moreover, electroactive injectable hydrogels supporting bone regeneration of the elderly will highly be desired in bone tissue engineering applications. Herein, thermosensitive nanoparticles were fabricated using chitosan/poly(N-isopropyl acrylamide) for simvastatin acid delivery. The nanoparticles were incorporated into electroactive injectable hydrogels based on aniline pentamer/silk fibroin/polyacrylamide containing vitamin C. The nanoparticles had thermosensitive properties as simvastatin acid had higher release rates at 37 than 23 °C without significant burst release. The hydrogels also revealed an appropriate gelation time, stable mechanical and rheological characteristics, high water absorbency, and proper biodegradability. In vitro studies indicated that the hydrogel was biocompatible and nontoxic, especially those containing drugs. Implantation of the hydrogels containing both simvastatin acid and vitamin C into the critical calvarial bone defect of the aged rat also demonstrated significant enhancement of bone healing after 4 and 8 weeks post-implantation. We found that the electroactive injectable hydrogels containing thermosensitive nanoparticles exhibited great potential for treating bone defects in the elderly ratsThis work has financially supported National Institute for Medical Research Development (NIMAD) Grant No. 972340. SCK has been the European Research Area Chair of the European Commission and the European Union Framework Programme for Research and Innovation Horizon 2020 (n◦ 668983 — FoReCaST and PTDC/BTM-ORG/28168/2017 of FCT, Portugal supported SCK
Mindfulness meditation targets transdiagnostic symptoms implicated in stress-related disorders: Understanding relationships between changes in mindfulness, sleep quality, and physical symptoms
Mindfulness-Based Stress Reduction (MBSR) is an 8-week meditation program known to improve anxiety, depression, and psychological well-being. Other health-related effects, such as sleep quality, are less well established, as are the psychological processes associated with therapeutic change. This prospective, observational study (n=213) aimed to determine whether perseverative cognition, indicated by rumination and intrusive thoughts, and emotion regulation, measured by avoidance, thought suppression, emotion suppression, and cognitive reappraisal, partly accounted for the hypothesized relationship between changes in mindfulness and two health-related outcomes: sleep quality and stress-related physical symptoms. As expected, increased mindfulness following the MBSR program was directly correlated with decreased sleep disturbance (r=-0.21, p=0.004) and decreased stress-related physical symptoms (r=-0.38, p<0.001). Partial correlations revealed that pre-post changes in rumination, unwanted intrusive thoughts, thought suppression, experiential avoidance, emotion suppression, and cognitive reappraisal each uniquely accounted for up to 32% of the correlation between the change in mindfulness and change in sleep disturbance and up to 30% of the correlation between the change in mindfulness and change in stress-related physical symptoms. Results suggest that the stress-reducing effects of MBSR are due, in part, to improvements in perseverative cognition and emotion regulation, two “transdiagnostic” mental processes that cut across stress-related disorders
Pseudomagnetic Moment in Graphene in Time-Dependent Electric Field
We study the dynamics of graphene ring in the presence of time-dependent electric field, where the Dirac particles in graphene ring interact with external electromagnetic fields. Using the Dirac Hamiltonian in electromagnetic field, we obtain the pseudomagnetic moment of the Dirac particles around a graphene ring. It is shown that the appeared pseudomagnetic moment term essentially can be in control by time-dependent electric field, and also it depends on the energy gap of graphene. It seems that one can construct a logic system in graphene and also in semiconductors by the pseudomagnetic moment term
The first fall is the hardest: the importance of peculiar galaxy dynamics at infall time for tidal stripping acting at the centers of groups and clusters
GalaxiesLarge scale structure and cosmolog
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